I have had my email set up through cox for years using pop.
All mail downloads nicely.
But now I can only add an email with imap set up.
My apple mail will not download the new imap email through this account except when I first start apple mail.
So right now I have to restart it all day long. Am I missing a setting?

Then I ran a test email address that was originally set up as pop. I NEVER really received email through this account. I turned it off and opened a new account (same address) but in imap. NOW in my Apple Mail I see a separate mailbox for the imap accounts AND I got a SPAM folder in this test run account almost immediately that appears to have mail in it from my other POP accounts.

In recent versions of the Mail.app, Apple has deliberately made it difficult for the user to create a new "POP" type account. For a new (and unsophisticated user), it's all-but impossible to find the solution.

You can workaround this.
Here's what to do:

In Mail.app, open preferences and click the "Accounts" tab.

Click the "+" to create a new account.

Mail will prompt you for a username and password.

Put in the username and email address, but deliberately ENTER AN INVALID PASSWORD (important).

Mail (of course) will try to contact the mail server and fail.

It will THEN present you with a dialog with more options, including a popup menu from which you can designate the new account to be "POP".

I had spam email do that with a pop email account as well in the past, so I just kept it an imap email account when I switched over to Apple. I personally don't think that's your problem, but I'm no email expert.

NOW how do I make the old email accounts go away.
I know to disable them and they are no longer in my mail list
but they still hang around in the Accounts list when I open that.
Even deleting them from the System/Library/Mail/mailboxes doesn't make them disappear.

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